Defects and plasticity in ultrastrong supercrystalline nanocomposites.

Supercrystalline nanocomposites are nanoarchitected materials with a growing range of applications but unexplored in their structural behavior. They typically consist of organically functionalized inorganic nanoparticles arranged into periodic structures analogous to crystalline lattices, including superlattice imperfections induced by processing or mechanical loading. Although featuring a variety of promising functional properties, their lack of mechanical robustness and unknown deformation mechanisms hamper their implementation into devices. We show that supercrystalline materials react to indentation with the same deformation patterns encountered in single crystals. Supercrystals accommodate plastic deformation in the form of pile-ups, dislocations, and slip bands. These phenomena occur, at least partially, also after cross-linking of the organic ligands, which leads to a multifold strengthening of the nanocomposites. The classic shear theories of crystalline materials are found to describe well the behavior of supercrystalline nanocomposites, which result to feature an elastoplastic behavior, accompanied by compaction.

A zone melting device for the in situ observation of directional solidification using high-energy synchrotron x rays.

Directional solidification (DS) is an established manufacturing process to produce high-performance components from metallic materials with optimized properties. Materials for demanding high-temperature applications, for instance in the energy generation and aircraft engine technology, can only be successfully produced using methods such as directional solidification. It has been applied on an industrial scale for a considerable amount of time, but advancing this method beyond the current applications is still challenging and almost exclusively limited to post-process characterization of the developed microstructures. For a knowledge-based advancement and a contribution to material innovation, in situ studies of the DS process are crucial using realistic sample sizes to ensure scalability of the results to industrial sizes. Therefore, a specially designed Flexible Directional Solidification (FlexiDS) device was developed for use at the P07 High Energy Materials Science beamline at PETRA III (Deutsches Elektronen-Synchrotron, Hamburg, Germany). In general, the process conditions of the crucible-free, inductively heated FlexiDS device can be varied from 6 mm/h to 12 000 mm/h (vertical withdrawal rate) and from 0 rpm to 35 rpm (axial sample rotation). Moreover, different atmospheres such as Ar, N2, and vacuum can be used during operation. The device is designed for maximum operation temperatures of 2200 °C. This unique device allows in situ examination of the directional solidification process and subsequent solid-state reactions by x-ray diffraction in the transmission mode. Within this project, different structural intermetallic alloys with liquidus temperatures up to 2000 °C were studied in terms of liquid-solid regions, transformations, and decompositions, with varying process conditions.

Small-fiber neuropathy and pain sensitization in survivors of pediatric acute lymphoblastic leukemia.

BACKGROUND: Chemotherapy-induced Peripheral Neuropathy (CIPN) of large-fibers affects up to 20% of survivors of pediatric acute lymphoblastic leukemia (ALL). We aimed to describe small-fiber toxicity and pain sensitization in this group. METHODS: In a cross-sectional, bicentric study we assessed 46 survivors of pediatric ALL (Mean age: 5.7 ± 3.5 years at diagnosis, median 2.5 years after therapy; males: 28). INCLUSION CRITERIA: ≥6 years of age, ≥3 months after last administration of Vincristine, and cumulative dose of Vincristine 12 mg/m2. We used a reduced version of the Pediatric-modified Total Neuropathy Score (Ped-mTNS) as bedside test and Quantitative Sensory Testing (QST) for assessment of small- and large-fiber neuropathy as well as pain sensitization. We employed Nerve Conduction Studies (NCS) as the most accurate tool for detecting large-fiber neuropathy. RESULTS: Fifteen survivors (33%) had abnormal rPed-mTNS values (≥4 points) and 5 survivors (11%) reported pain. In QST, the survivor group showed significant (p < 0.001) inferior large-fiber function and pain sensitization when compared to healthy matched peers. We identified deficits of vibration in 33 (72%) and tactile hypoesthesia in 29 (63%), hyperalgesia to blunt pressure in 19 (41%), increased mechanical pain sensitivity in 12 (26%) and allodynia in 16 (35%) of 46 survivors. Only 7 survivors (15%) had pathologic NCS. CONCLUSION: QST is a sensitive tool that revealed signs of large-fiber neuropathy in two thirds, small-fiber neuropathy and pain sensitization in one third of survivors. Prospective studies using QST in pediatric oncology may help to elucidate the pathophysiology of small-fiber neuropathy and pain sensitization as well as their relevance for quality of survival.

Quantitative sensory testing profiles in children, adolescents and young adults (6-20 years) with cerebral palsy: Hints for a neuropathic genesis of pain syndromes.

INTRODUCTION: Many patients with cerebral palsy (CP) suffer chronic pain as one of the most limiting factors in their quality of life. In CP patients, pain mechanisms are not well understood, and pain therapy remains a challenge. Quantitative sensory testing (QST) might provide unique information about the functional status of the somatosensory system and therefore better guide pain treatment. OBJECTIVES: To understand better the underlying pain mechanisms in pediatric CP patients, we aimed to assess clinical and pain parameters, as well as QST profiles, which were matched to the patients' cerebral imaging pathology. PATIENTS AND METHODS: Thirty CP patients aged 6-20 years old (mean age 12 years) without intellectual impairment underwent standardized assessments of QST. Cerebral imaging was reassessed. QST results were compared to age- and sex-matched controls (multiple linear regression; Fisher's exact test; linear correlation analysis). RESULTS: CP patients were less sensitive to all mechanical and thermal stimuli than healthy controls but more sensitive to all mechanical pain stimuli (each p < 0.001). Fifty percent of CP patients showed a combination of mechanical hypoesthesia, thermal hypoesthesia and mechanical hyperalgesia; 67% of CP patients had periventricular leukomalacia (PVL), which was correlated with mechanic (r = 0.661; p < 0.001) and thermal (r = 0.624; p = 0.001) hypoesthesia. CONCLUSION: The combination of mechanical hypoesthesia, thermal hypoesthesia and mechanical hyperalgesia in our CP patients implicates lemniscal and extralemniscal neuron dysfunction in the thalamus region, likely due to PVL. We suspect that extralemniscal tracts are involved in the original of pain in our CP patients, as in adults.

Difficulties in screening for peripheral neuropathies in children with diabetes.

AIMS: To assess the diagnostic utility of a novel abbreviated monofilament test in comparison with the tuning fork test to detect diabetic peripheral neuropathy in children. METHODS: A total of 88 children with Type 1 diabetes mellitus were screened for diabetic peripheral neuropathy using the monofilament test and the tuning fork. Nerve conduction studies were performed according to the 'gold standard' for neuropathy. We assessed the diagnostic utility and inter-rater agreement of the two screening methods. RESULTS: A total of 43 (49%) children (aged 6-18 years) had at least one abnormal nerve conduction study result. Diagnostic utility and inter-rater agreement were very low for both screening methods. The monofilament test yielded a sensitivity of 18% and a specificity of 80%. The tuning fork yielded a sensitivity of 0% and a specificity of 98%. CONCLUSION: The present study found that an abbreviated monofilament test has low diagnostic utility for the detection of early diabetic peripheral neuropathy because of its low reliability. The problem of reliability needs to be more thoroughly addressed in order to improve the screening procedures in diabetes management in childhood and adolescence.

Impact of beta-amyloid-specific florbetaben PET imaging on confidence in early diagnosis of Alzheimer's disease.

BACKGROUND: Early diagnosis of Alzheimer's disease (AD) may be corroborated by imaging of beta-amyloid plaques using positron emission tomography (PET). Here, we performed an add-on questionnaire study to evaluate the relevance of florbetaben imaging (BAY 949172) in diagnosis and consecutive management of probable AD patients. METHODS: AD patients with a clinical diagnosis in accordance with the NINCDS-ADRDA criteria or controls were imaged using florbetaben. Referring physicians were asked on a voluntary basis about their confidence in initial diagnosis, significance of PET imaging results, and their anticipated consequences for future patient care. RESULTS: 121 questionnaires for probable AD patients and 80 questionnaires for controls were evaluated. In 18% of patients who had initially received the diagnosis of probable AD, PET scans were rated negative, whereas in controls 18% of scans were positive. An increase in confidence in the initial diagnosis was frequently reported (80%). Imaging results had a significant impact on the intended patient care, as judged by the referring physicians; this was most prominent in those patients with a contradicting scan and/or a low confidence in the initial diagnosis. CONCLUSION: Florbetaben amyloid imaging increases the overall confidence in diagnosis of AD and may frequently influence clinical decisions and patient management.

Genomic chondrocyte culture profiling by array-CGH, interphase-FISH and RT-PCR.

OBJECTIVE: In vitro expansion is an important step to acquire sufficient cells in human tissue engineering technologies. The high number of chondrocytes needed for human articular cartilage implants requires in vitro expansion of the primary cells, bearing a theoretical risk of in vitro induced changes in the genomes. To gain more insights into this situation, model cultures were prepared and analyzed. DESIGN: 25 chondrocyte cell DNA samples from nine donors were analyzed by array comparative genomic hybridization (aCGH) on whole genome level and 28 chondrocyte cell samples from 16 individuals were analyzed by fluorescence in situ hybridization (FISH) on single cell level. The expanded cells were further characterized upon the chondrocytic mRNA phenotype by reverse-transciptase polymerase chain reaction (RT-PCR). RESULTS: The molecular karyotyping results revealed autosomal stability, but all male samples analyzed by aCGH displayed a variable loss of the Y-chromosome. These data were confirmed by FISH-experiments and suggest an age dependant effect toward the loss of the Y-chromosome in cultured chondrocytes. RT-PCR data for the mRNAs from collagen types I, II, and aggrecan and the pro-inflammatory cytokine interleukin-1ß (IL-1ß) did not reveal any correlation of transcriptional activity in cultures with Y-chromosome losses, nor were there statistically significant differences between cells from female and male donors. CONCLUSIONS: While cells of male origin may suffer from an age-related loss of the Y-chromosome, there was no indication of a functional impairment. The data suggest some caution toward applying proliferative steps when considering chondrocytes from elderly male patients for tissue engineering approaches.

[Please don't hurt me!: a plea against invasive procedures in children and adolescents with complex regional pain syndrome (CRPS)]. / Bitte nicht noch mehr verletzen! : Plädoyer gegen eine invasive Schmerztherapie bei Kindern mit komplexem regionalem Schmerzsyndrom (CRPS).

BACKGROUND: Complex regional pain syndrome (CRPS; formerly known as Morbus Sudeck/reflex dystrophy) is diagnosed in children and adolescents, but the clinical presentation is often atypical. Unfortunately, potentially harmful, invasive treatments are used in pediatric patients. PATIENTS AND METHODS: A retrospective chart study of pediatric chronic pain patients with CRPS was performed. RESULTS: Over the course of 6 years, 37 (35 girls) children and adolescents took part in a multidisciplinary chronic pain inpatient program. At admission, patients took on average 4.4 (range 1-10) different medications and 29 different pharmaceuticals were used overall. Prior to admission, invasive pain treatments were performed without success in 16 of the children (43%). At least 13 children received two or more invasive treatments. Although sympathetic blocks were most prevalent, operations and regional anesthesia were also used. CONCLUSION: Despite a lack of evidence for invasive procedures, these continue to be used in children and adolescents with CRPS, who later respond positively to conventional treatment. The English full-text version of this article is available at SpringerLink (under "Supplemental").

Childhood diabetic neuropathy: functional impairment and non-invasive screening assessment.

AIM: Sensory diabetic neuropathy, determined by nerve conduction studies, is common in children with Type 1 diabetes. Diabetic neuropathy diagnoses are rarely made in paediatric daily care because they are asymptomatic, vibration detection is mostly normal and nerve-conduction testing is impractical. The present study aims to: (1) describe somatosensory dysfunction in children with diabetes, (2) test whether diabetes duration and HbA(1c) are related to somatosensory dysfunction and (3) identify the best screening test for large-fibre dysfunction, as indicated by nerve conduction studies. METHODS: Forty-five children (age 13.2 ± 2.5 years) with Type 1 diabetes for 6.7 ± 2.5 years and matched control subjects were assessed by neurological examinations, nerve conduction tests and quantitative sensory testing on the feet using the protocol of the German Research Network on Neuropathic Pain. Abnormal nerve conduction was used as gold standard to define neuropathies. RESULTS: We found a high prevalence of mechanical (38%) and thermal (24%) hypoesthesia often associated with hyperalgesia (47%). Tactile hypoesthesia (33%) was more frequent than pallhypaesthesia (11%). Only cold detection and mechanical pain thresholds were related to HbA(1c). Tactile hypoesthesia had the highest sensitivity (75%), specificity (89%) and positive (75%) and negative (89%) predictive values for neuropathies defined by nerve conduction tests (31% abnormal). CONCLUSIONS: Almost half of the children with diabetes have subclinical large- and small-fibre neuropathies. Tactile detection was better than vibration for neuropathy assessment. Quantitative sensory testing is a valuable tool for assessment of neuropathy as well as a target of interventional studies in children with diabetes.

Developmental and sex differences in somatosensory perception--a systematic comparison of 7- versus 14-year-olds using quantitative sensory testing.

There are controversial discussions regarding developmental- and sex-related differences in somatosensory perception, which were found, eg, when comparing younger children (6-8 years), older children (9-12 years), and adolescents (13-16 years) using quantitative sensory testing (QST). The aim of our current study was to systematically assess the impact of age and sex using the QST protocol of the German Research Network on Neuropathic Pain (DFNS). QST, including thermal and mechanical detection and pain thresholds, was assessed in 86 healthy 7-year-old children (42 girls and 44 boys) and 87 healthy 14-year-old adolescents (43 girls and 44 boys). The sample size was calculated a priori to detect medium-sized effects as found in the previous studies with adequate power. Developmental and sex differences were tested using univariate analysis of variance. Children were more sensitive to most pain stimuli, except cold pain stimuli, compared with adolescents, but did not differ in mechanical and thermal detection thresholds except in regard to cold stimuli. Sex had an impact only on warm detection, with girls being more sensitive. There were no interactions between age and sex. In conclusion, developmental changes during the puberty appear to influence pain perception, whereas sex effects in childhood are negligible. At present, it is not clear what brings about the differences between adult men and women that are apparent in epidemiological studies. Our results contradict the hypothesis that differences in peripheral nerve-fiber functioning underlie sex effects.

[Comparable disorder of the body schema in patients with complex regional pain syndrome (CRPS) and phantom pain]. / Vergleichbare Störung des Körperschemas bei Patienten mit komplexem regionalem Schmerzsyndrom (CRPS) oder Phantomschmerz.

In patients with complex regional pain syndrome (CRPS) a disruption of the body schema has been shown in an altered cortical representation of the hand and in delayed reaction times (RT) in the hand laterality recognition task. However, the role of attentional processes or the effect of isolated limb laterality training has not yet been clarified. The performance of healthy subjects (n = 38), CRPS patients (n = 12) and phantom limb pain (PLP) patients (n = 12) in a test battery of attentional performance (TAP) and in a limb laterality recognition task was compared and the effect of limb laterality training in CRPS patients and healthy subjects evaluated. The RTs of both CRPS and PLP patients were significantly slower than those of healthy subjects despite normal TAP values. The CRPS and PLP patients showed bilaterally delayed RTs. Through training RTs improved significantly but the RTs of CRPS patients remained slower than those of healthy subjects. In this study an equal disruption of the body schema was found in both CRPS and PLP patients which cannot be accounted for by attentional processes. For CRPS patients this disorder cannot be fully reversed by isolated limb laterality recognition training.

Cost impact of prospective HLA-B*5701-screening prior to abacavir/lamivudine fixed dose combination use in Germany.

OBJECTIVE: Avoiding abacavir in HIV-infected patients tested positive for HLA-B*5701 reduces the risk of abacavir hypersensitivity reaction (ABC-HSR). Our aim was to assess the costs of clinically suspected HSR and to estimate potential cost savings of implementing prospective HLA-B*5701-screening for HIV-infected patients initiating abacavir/lamivudine fixed-dose combination (ABC/3TC FDC) compared to initiating respective treatment without screening. METHODS: Employing a decision tree model the expected HSR-related costs of screening vs. no screening were estimated from the societal and healthcare payer perspective (reference year 2007). A retrospective standardized assessment of all clinically suspected ABC-HSR cases without screening at 5 German HIV-centres was performed to measure resource consumption. In- and outpatient care, discarded ABC/3TC FDC and concomitant medication were considered. Direct resource utilization was valued using German fees (EBM, G-DRGs). Indirect costs were measured with the human capital approach. Estimates for the HLA-B*5701-prevalence, HSR-incidence, and hospitalization rate were based on clinical trials and cohorts and it was assumed that screening reduces the incidence of clinically suspected ABC-HSR from 10% to 0.5%. RESULTS: Thirty-two ABC-HSR cases were identified from 1998 to 2007. Mean direct and total costs per clinically suspected HSR case were Euro 1,362 and Euro 2,235, respectively. Hospital costs contributed 63.3% to direct costs. Potential cost savings when implementing genetic screening were estimated at Euro 44 and Euro 127 per screened patient, from a healthcare payer or societal perspective. CONCLUSION: HLA-B*5701 screening prior to ABC/3TC FDC initiation prevents significant HSR-related costs per screened patient and is likely to lead to overall net savings.

Reference values for quantitative sensory testing in children and adolescents: developmental and gender differences of somatosensory perception.

The Quantitative Sensory Testing (QST) protocol of the German research network on neuropathic pain (DFNS) encompassing all somatosensory modalities assesses the functioning of different nerve fibers and of central pathways. The aim of our study was: (1) to explore, whether this QST protocol is feasible for children, (2) to detect distribution properties of QST data and the impact of body site, age and gender and (3) to establish reference values for QST in children and adolescents. The QST protocol of the DFNS with modification of instructions and pain rating was used in 176 children aged 6.12-16.12years for six body sites. QST was feasible for children over 5years of age. ANOVAs revealed developmental, gender and body site differences of somatosensory functions similar to adults. The face was more sensitive than the hand and/or foot. Younger children (6-8years) were generally less sensitive to all thermal and mechanical detection stimuli but more sensitive to all pain stimuli than older (9-12years) children, whereas there were little differences between older children and adolescents (13-17years). Girls were more sensitive to thermal detection and pain stimuli, but not to mechanical detection and pain stimuli. Reference values differ from adults, but distribution properties (range, variance, and side differences) were similar and plausible for statistical factors. Our results demonstrate that the full QST protocol is feasible and valid for children over 5years of age with their own reference values.

High-Throughput Omics Technologies: Potential Tools for the Investigation of Influences of EMF on Biological Systems.

The mode of action of a huge amount of agents on biological systems is still unknown. One example where more questions than answers exist is covered by the term electromagnetic fields (EMF). Use of wireless communication, e.g. mobile phones, has been escalated in the last few years. Due to this fact, a lot of discussions dealt with health consequences of EMF emitted by these devices and led to an increased investigation of their effects to biological systems, mainly by using traditional methods. Omics technologies have the advantage to contain methods for investigations on DNA-, RNA- and protein level as well as changes in the metabolism.This literature survey is an overview of the available scientific publications regarding biological and health effects of EMF and the application of new high-throughput technologies. The aim of the study was to analyse the amount and the distribution of these technologies and to evaluate their relevance to the risk analysis of EMF. At present, only transcriptomics is able to analyse almost all of the specific molecules. In comparison to ionising radiation, fewer articles dealt with health effects of EMF. Interestingly, most of the EMF articles came from European institutions.Although omics techniques allow exact and simultaneous examinations of thousands of genes, proteins and metabolites in high-throughput technologies, it will be an absolute prerequisite to use standardised protocols and to independently validate the results for comparability and eventually for sound standing statements concerning possible effects of agents like EMF on biological systems.

Paroxysmal hemicrania in children--symptoms, diagnostic criteria, therapy and outcome.

Whereas paroxysmal hemicrania (PH) is studied extensively in adults, even case reports of PH in children are rare. We present the first prospective follow-up study on PH in children. Our aim was to investigate whether differences exist between paediatric and adult patients. We assessed all children with chronic headache who were referred to our paediatric out-patient pain clinic within 3 years based on interviews and validated questionnaires. Among 628 patients we found five children with PH (0.8%) and three with probable PH (0.5%), in total 1.3%. Pain characteristics, autonomic symptoms and treatment response to indomethacin were similar to adult PH patients. Our results demonstrate that the International Headache Society classification of PH is also applicable to children. We suspect that PH has been underdiagnosed in children and therefore suboptimally treated thus far.

Parents' perspective on symptoms, quality of life, characteristics of death and end-of-life decisions for children dying from cancer.

BACKGROUND: In the present study, we investigated the situation of children who had succumbed to their malignancy in Germany as perceived by their parents. Specifically, we were interested in bereaved parents' perspective on five essential areas: 1) symptoms and quality of life, 2) characteristics of the child's death, 3) anticipation of their child's death and care delivery, 4) end-of-life decisions and 5) impact of the child's death on the parents and perceived social support by the health care team. MATERIALS AND METHODS: We contacted all existing departments for paediatric oncology in the German federal state of Nordrhein Westfalen and asked them to contact all parents for participation in our study who had lost their child to cancer in 1999 and 2000. Upon agreement, we interviewed the parents utilising a validated semi-structured interview on distressing symptoms and quality of life of their children during the end-of-life care period. RESULTS: Six of the 19 departments agreed to participate. Parents of 48 children (31 boys, 17 girls) were interviewed. The main distressing symptoms were fatigue, pain, loss of appetite, and dyspnoea according to the parents. While parents perceived pain and constipation to have been treated successfully, loss of appetite and anxiety were not treated effectively. 75% of the children died due to a progression of their malignancy. Of these, 50% obtained cancer-directed therapy at the end of life, which was negatively rated by the parents in hindsight. 48% of the children died at home even though 88% of the parents chose 'at home' as the most appropriate locale of death in hindsight. Parents anticipated their child's death on average 9 weeks prior to the child's death. 41% of the parents provided palliative home care for their child and the majority (88%) rated the quality of care as good or very good. 64% discussed end-of-life decisions with the health care team, 36% did not have a discussion. Parents were clearly affected by their child's death. However, 15% of the parents were not contacted by the health care team following the child's death. CONCLUSIONS: The present study demonstrated that psychological symptoms (e.g. anxiety) are frequent symptoms in the end-of-life care period and cause severe suffering in the children. Questions in terms of benefits and costs of cancer-directed therapy in the end-of-life care period need to be addressed in future prospective studies. Parents' perspective on their child's death and related end-of-life decisions highlighted the importance of communication between parents and the health care team. Future studies need to investigate potential barriers in the communication between parents and the team to optimise end-of-life decisions and hence, reduce parents' long-term distress. In line with the previous, the present data demonstrated that there is still a lack of routine contact from the health care team following the child's death despite existing guidelines. Research is therefore needed into the implementation of guidelines for routine contact into clinical practice following a child's death.

[Unique children -- unique headaches. Case reports of pediatric headache patients from an outpatient children's pain department]. / Individuelle Kinder -- individuelle Kopfschmerzen. Fallbeispiele kindlicher Kopfschmerzen aus einer multidisziplinären Kinderschmerzambulanz.

In the industrialized nations headache prevalence is increasing in children and adolescents. The nosologic classification determines the therapeutic strategy to follow. Three case reports illustrate the optimal cooperation of both a pediatric outpatient pain clinic and a pediatric psychosomatic pain clinic. We report on (1) a girl aged 2 years and 7 months with a 4-month history of headache episodes lasting about 15 min each with concomitant symptoms; (2) an 11-year-old boy with Schimmelpenning-Feuerstein-Mims syndrome, symptomatic focal epilepsy, psychomotor retardation, mild postinfectious internal hydrocephalus, and repeated heat-triggered episodes of right-sided headache beginning suddenly with a duration of 5-30 min and concomitant flush of his hemiface; and (3) a 12-year-old boy who for about 2 years has suffered from "migraine" 3 times a week, significantly impairing his quality of life. We discuss the patients' courses, diagnostic pitfalls, and therapeutic options. For the optimal treatment of children with headache not easily fitting into one of the categories, with significant comorbidity present, or if there is no adequate response to therapy conforming with guidelines, the help of an interdisciplinary pediatric pain clinic is invaluable.

Target anticipation and impairment of smooth pursuit eye movements in schizophrenia.

A reduced gain of smooth pursuit eye velocity has frequently been reported in schizophrenic patients. With respect to predictable stimuli, this could be due to a deficit in predicting the target path. To determine this contribution to smooth pursuit eye movement performance, we analyzed the ocular smooth pursuit response to a sinusoidally moving target that was suddenly stopped after some cycles of regular movement. Horizontal eye movements were recorded with infrared reflection oculography in a group of 17 schizophrenic in-patients and 16 age-matched healthy subjects for controls. The patients exhibited a reduced gain of smooth pursuit velocity, but phase lag was not different from the control group. After the unpredictable stop of target movement, predictive sinusoidal smooth pursuit was maintained for 150 to 200 ms in both groups. The resulting maximal position and velocity error was larger in the patient group. In conclusion, schizophrenic patients were able to generate a normal anticipatory component of smooth pursuit and to switch it off in response to external demands. They showed, however, an increased velocity of anticipatory pursuit, which might be used to compensate for the primary deficit of smooth pursuit velocity frequently found in schizophrenics.